iOS:UINavigationBar appearance与UIBarButtonItem appearance简介

[UINavigationBar appearance]与[UIBarButtonItem appearance]使用方法基本相同。

• [UIBarButtonItem appearance] 设置导航条左右两边item的文字样式
• [UINavigationBar appearance] 设置导航条title，整个导航条颜色背景等
  方法总结：

UINavigationBar:

• 1.设置颜色 [[UINavigationBar appearance] setBarTintColor:[UIColor colorWithRed:0 green:0 blue:0 alpha:1]]; [[UINavigationBar
  appearance] setBarTintColor:UIColorFromRGB(0x067AB5)];

• 2.设置导航文字颜色 [[UINavigationBar appearance] setTintColor:[UIColor whiteColor]];

• 3.设置导航背景 [[UINavigationBar appearance] setBackgroundImage:[UIImage imageNamed:@”nav_bg.png”] forBarMetrics:UIBarMetricsDefault];

UIBarButtonItem:

• 1.修改背景： [[UIBarButtonItem appearance] setBackButtonBackgroundImage:leftButton
  forState:0
  barMetrics:UIBarMetricsDefault];

• 2.修改字体，阴影，字体颜色 NSDictionary* textAttributes = [NSDictionary dictionaryWithObjectsAndKeys:
  BAR_BUTTON_TITLE_TEXT_COLOR,UITextAttributeTextColor,
  BAR_BUTTON_TITLE_FONT,UITextAttributeFont,
  BAR_BUTTON_TITLE_SHADOW_COLOR,UITextAttributeTextShadowColor,
  [NSValue valueWithCGSize:CGSizeMake(1, 1)],UITextAttributeTextShadowOffset,
  nil]; [[UIBarButtonItem appearance] setTitleTextAttributes:textAttributes forState:0];

• 3.修改UIBarButtonItem中文字的位置： [[UIBarButtonItem appearance]
  setBackButtonTitlePositionAdjustment:UIOffsetMake(2, -1)
  forBarMetrics:UIBarMetricsDefault];